Forisomes: Mechano-Proteins that Exert Force in Contraction and Expansion

M. Knoblauch, G.A. Noll, D. Prüfer, H. Jaag, M.E. Fontanellaz, I. Schneider-Hüther, A.J.E. van Bel and W.S. Peters
Fraunhofer Institute IME, DE

Keywords: ATP-independent actuator, microfluidic system

Abstract:
Motor-proteins are the basis of the dynamic three dimensional organization of the living cell. Most motor-proteins are driven by energetically favorable reactions such as ATP hydrolysis. We here describe anisotropic contractility in forisomes, protein bodies from higher plant cells, that is energized by changes of the free Ca2+ concentration in the nanomolar range and, alternatively, by alterations in pH. The rapid reaction is reversible; mechanic forces of similar magnitude are exerted in contraction and expansion. Individual forisomes can be isolated and kept fully functional in vitro. Forisomes represent a previously unknown class of mechano-protein with properties that invite their use in micro- and nanobiotechnological devices.

Nanotech 2004 Conference Technical Program Abstract